1. Technical Field
The present disclosure relates in general to wireless communication devices and in particular to frequency offset compensation in wireless communication devices.
2. Description of the Related Art
In the process of cell acquisition for Long Term Evolution (LTE), there is a need to accurately estimate and compensate for the frequency offset (error) between the mobile station local oscillator and the base station local oscillator. Effective compensation requires accurate estimation of the frequency offset, otherwise residual frequency error will cause spectral shift in the compensated signal and cell detection performance will degrade. Furthermore, it is desirable to be able to use a signal which is known a priori to the mobile station (e.g. synchronization signals such as LTE Primary Synchronization Channel (PSCH)) such that the frequency error estimate is available during the initial cell acquisition process. However, synchronization signals are typically transmitted at low power and/or low duty factor, and thus, producing an accurate frequency error estimate can be challenging in the presence of interference from other cells. Furthermore, timing offsets between ideal matched filter sampling offset and an actual sampling offset presents a major challenge to conventional approaches to frequency offset estimation.